A wide variety of medical treatments are at least partially performed through the delivery and introduction of therapeutic compositions to a treatment location. Lower urinary tract health is an increasingly important health issue, e.g., based on an aging population. Prostate disease, for example, is a significant health risk for males. Diseases of the prostate include prostatitis, benign prostatic hyperplasia (BPH, also known as benign prostatic hypertrophy), and prostatic carcinoma.
Prostatitis is an inflammation of the prostate gland. Prostatitis is caused by bacterial infection in many instances, in which case treatment generally includes antimicrobial medication. Noninfectious forms of prostatitis are treated by other means such as administration of an alpha-1-adrenoreceptor antagonist drug to relax the muscle tissue in the prostate and reduce the difficulty in urination. Benign prostatic hypertrophy (BPH) is a very common disorder affecting an estimated 12 million men in the United States alone. BPH is a non-cancerous condition characterized by enlargement of the prostate, obstruction of the urethra, and gradual loss of bladder function. BPH may be treated with a number of therapeutic modalities including surgical and medical methods, depending on severity of symptoms. Treatments range from “watchful waiting” for men with mild symptoms, to medications, to surgical procedures.
Surgical methods used to relieve the symptoms of BPH include methods of promoting necrosis of tissue that blocks the urethra. Hyperthermic methods, for example, use the application of heat to “cook” tissue and kill the cells. The necrosed tissue is gradually absorbed by the body. Several methods of applying heat or causing necrosis have been demonstrated, including direct heat (transurethral needle ablation, or TUNA), microwave (transurethral microwave treatment, or TUMT), ultrasound (high-intensity focused ultrasound, or HIFU), electrical vaporization (transurethral electrical vaporization of the prostate, or TUEVP) and laser ablation (visual laser ablation of the prostate, or VLAP), among others.
Chemical ablation (chemoablation) techniques for promoting prostate tissue necrosis have also been considered. In one chemical ablation technique, absolute ethanol is injected transurethrally into the prostate tissue. This technique is known as transurethral ethanol ablation of the prostate (TEAP). The injected ethanol causes cells of the prostate to burst, killing the cells. The prostate shrinks as the necrosed cells are absorbed.
To inject the prostate, a transuretheral flexible endoscopic probe is typically directed to the area of interest. Because a flexible endoscope is rotated inside bends the injection tube will tend to uncontrollably rotate inside the channel of the endoscope because it does not have equal bending stiffness in all degrees of movement. Moreover, the articulating section of the flexible endoscope can typically only bend on one direction making compound bends impossible. This is a problem in the anatomy around the prostate. Therefore there is a need to fix the injection tube in a preselected orientation so as to enable an injection in the desired direction.